.page-about {
  --about-rail-w: 13rem;
  --about-gap: clamp(1.5rem, 3.5vw, 3rem);
  background: var(--c-void);
  color: var(--c-starlight);
  font-family: var(--font-body);
  overflow-x: clip;
}

.page-about p {
  margin: 0 0 1rem;
  line-height: var(--lh-body);
}

.page-about .about-crumb {
  padding-block: 1.25rem 0;
}

.page-about .breadcrumb__item {
  color: var(--c-mist);
  font-size: var(--fs-note);
  letter-spacing: 0.04em;
}

.page-about .breadcrumb__item[aria-current="page"] {
  color: var(--c-cyan);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding-block: clamp(2rem, 6vw, 4rem) clamp(2.5rem, 7vw, 5rem);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: -20% -25% auto -25%;
  height: 130%;
  background:
    radial-gradient(55% 45% at 76% 20%, rgba(185, 167, 255, 0.22), transparent 70%),
    radial-gradient(42% 38% at 10% 76%, var(--c-glow-cyan), transparent 72%);
  opacity: 0.6;
  pointer-events: none;
  z-index: 0;
}

.page-about .about-hero__grid {
  position: relative;
  z-index: 1;
  display: grid;
  gap: var(--sp-5);
  min-width: 0;
}

.page-about .about-hero__copy {
  min-width: 0;
}

.page-about .about-hero .eyebrow {
  color: var(--c-cyan);
  font-family: var(--font-mono);
  letter-spacing: var(--track-mono);
  font-size: var(--fs-note);
  margin: 0 0 0.75rem;
}

.page-about .about-hero__title {
  font-family: var(--font-head);
  font-size: clamp(2.25rem, 6.5vw, 4.25rem);
  line-height: 1.08;
  letter-spacing: var(--track-head);
  font-weight: 800;
  margin: 0 0 1.25rem;
  color: var(--c-starlight);
}

@supports (background-clip: text) or (-webkit-background-clip: text) {
  .page-about .about-hero__title {
    background: linear-gradient(100deg, var(--c-starlight) 12%, var(--c-violet) 62%, var(--c-cyan) 100%);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
  }
}

.page-about .about-hero__lede {
  font-size: var(--fs-body);
  color: var(--c-starlight);
  max-width: 34em;
  margin-bottom: 0.9rem;
}

.page-about .about-hero__lede--sub {
  color: var(--c-mist);
  font-size: var(--fs-note);
  line-height: 1.8;
  border-left: 2px solid var(--c-line);
  padding-left: 0.9rem;
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1.5rem;
}

.page-about .about-hero__figure {
  margin: 0;
  min-width: 0;
}

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border-radius: var(--r-lg);
  border: 1px solid var(--c-line);
  box-shadow: 0 30px 80px -46px var(--c-glow-violet);
}

/* ---------- 布局：索引栏 + 内容流 ---------- */
.page-about .about-layout {
  display: grid;
  gap: var(--about-gap);
  padding-block: clamp(1rem, 3vw, 2rem) clamp(3rem, 8vw, 6rem);
  min-width: 0;
}

.page-about .about-rail {
  min-width: 0;
  padding: 0.9rem 1rem;
  border: 1px solid var(--c-line-soft);
  border-radius: var(--r-md);
  background: rgba(17, 26, 51, 0.72);
}

.page-about .about-rail__title {
  margin: 0 0 0.6rem;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: var(--track-mono);
  color: var(--c-mist);
  text-transform: uppercase;
}

.page-about .about-rail .side-rail__list {
  display: flex;
  gap: 0.5rem;
  margin: 0;
  padding: 0 0 0.25rem;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-rail .side-rail__link {
  display: block;
  white-space: nowrap;
  padding: 0.4rem 0.8rem;
  border-radius: var(--r-pill);
  border: 1px solid transparent;
  font-size: var(--fs-note);
  font-family: var(--font-mono);
  letter-spacing: 0.06em;
  color: var(--c-mist);
  text-decoration: none;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .about-rail .side-rail__link:hover,
.page-about .about-rail .side-rail__link:focus-visible {
  color: var(--c-void);
  background: var(--c-cyan);
  border-color: var(--c-cyan);
  outline: none;
}

.page-about .about-flow {
  min-width: 0;
}

/* ---------- 章节骨架 ---------- */
.page-about .about-chapter {
  padding-block: clamp(1.5rem, 4vw, 2.5rem) clamp(2rem, 5vw, 3.5rem);
  min-width: 0;
}

.page-about .about-chapter + .about-chapter {
  margin-top: clamp(1rem, 3vw, 2rem);
}

.page-about .about-chapter__head {
  margin-bottom: clamp(1.25rem, 3vw, 2rem);
}

.page-about .about-chapter .section-index {
  margin: 0 0 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: var(--track-mono);
  color: var(--c-violet);
}

.page-about .about-chapter__title {
  position: relative;
  font-family: var(--font-head);
  font-size: var(--fs-index);
  line-height: var(--lh-head);
  letter-spacing: var(--track-head);
  font-weight: 700;
  margin: 0;
  padding-left: 0;
}

.page-about .about-chapter__title::after {
  content: "";
  display: block;
  width: 3.5rem;
  height: 2px;
  margin-top: 0.85rem;
  background: linear-gradient(90deg, var(--c-cyan), transparent);
}

.page-about .about-chapter__intro {
  margin: 0.9rem 0 0;
  max-width: 40em;
  font-size: var(--fs-body);
  color: var(--c-mist);
}

/* 奶油纸章节 */
.page-about .about-chapter--paper {
  background: var(--c-paper);
  color: var(--c-ink);
  border-radius: var(--r-lg);
  padding: clamp(1.5rem, 4vw, 2.75rem);
  box-shadow: 0 26px 60px -44px rgba(0, 0, 0, 0.9);
}

.page-about .about-chapter--paper .section-index {
  color: var(--c-signal);
}

.page-about .about-chapter--paper .about-chapter__title {
  color: var(--c-ink);
}

.page-about .about-chapter--paper .about-chapter__title::after {
  background: linear-gradient(90deg, var(--c-signal), rgba(255, 107, 74, 0));
}

.page-about .about-chapter--paper .about-chapter__intro {
  color: rgba(42, 31, 26, 0.72);
}

/* 星云带章节 */
.page-about .about-chapter--band {
  background: linear-gradient(155deg, rgba(17, 26, 51, 0.96), rgba(7, 11, 24, 0.6));
  border: 1px solid var(--c-line);
  border-radius: var(--r-lg);
  padding: clamp(1.5rem, 4vw, 2.75rem);
}

/* ---------- 起点 ---------- */
.page-about .about-origin {
  display: grid;
  gap: var(--sp-4);
  min-width: 0;
}

.page-about .about-origin__text p {
  font-size: var(--fs-body);
  color: var(--c-starlight);
}

.page-about .about-origin__text p + p {
  color: var(--c-mist);
  font-size: var(--fs-note);
  line-height: 1.85;
}

.page-about .about-origin__points {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.85rem;
}

.page-about .about-origin__point {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 0.2rem 0.85rem;
  padding: 0.9rem 1rem;
  border-radius: var(--r-md);
  border: 1px solid var(--c-line-soft);
  background: rgba(17, 26, 51, 0.55);
}

.page-about .about-origin__no {
  grid-row: span 2;
  font-family: var(--font-mono);
  font-size: 1rem;
  line-height: 1.4;
  color: var(--c-cyan);
  align-self: start;
}

.page-about .about-origin__label {
  font-family: var(--font-head);
  font-weight: 700;
  letter-spacing: 0.04em;
  font-size: var(--fs-sub);
  color: var(--c-starlight);
}

.page-about .about-origin__desc {
  font-size: var(--fs-note);
  line-height: 1.75;
  color: var(--c-mist);
}

/* ---------- 索引方法 ---------- */
.page-about .about-method {
  display: grid;
  gap: var(--sp-4);
  min-width: 0;
}

.page-about .about-method__list {
  list-style: none;
  margin: 0;
  padding: 0;
  counter-reset: none;
}

.page-about .about-method__item {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 0.35rem 1rem;
  padding-block: 1.1rem;
  border-top: 1px solid rgba(42, 31, 26, 0.18);
}

.page-about .about-method__item:last-child {
  border-bottom: 1px solid rgba(42, 31, 26, 0.18);
}

.page-about .about-method__no {
  font-family: var(--font-mono);
  font-size: 1.25rem;
  line-height: 1.2;
  color: var(--c-signal);
  letter-spacing: 0.08em;
}

.page-about .about-method__title {
  margin: 0 0 0.35rem;
  font-family: var(--font-head);
  font-size: var(--fs-sub);
  letter-spacing: 0.03em;
  color: var(--c-ink);
}

.page-about .about-method__body p {
  margin: 0;
  font-size: var(--fs-note);
  line-height: 1.8;
  color: rgba(42, 31, 26, 0.78);
}

.page-about .about-method__scene {
  align-self: start;
  padding: 1.1rem 1.15rem;
  border-radius: var(--r-md);
  border: 1px dashed rgba(42, 31, 26, 0.3);
}

.page-about .about-method__scene-title {
  margin: 0 0 0.75rem;
  font-size: var(--fs-note);
  letter-spacing: 0.06em;
  color: rgba(42, 31, 26, 0.7);
}

.page-about .about-method__scene .tag {
  border-color: rgba(42, 31, 26, 0.28);
  color: var(--c-ink);
  background: rgba(42, 31, 26, 0.06);
}

.page-about .about-method__scene .tag--cyan {
  background: rgba(69, 240, 224, 0.22);
  border-color: rgba(42, 31, 26, 0.32);
}

.page-about .about-method__scene .tag--gold {
  background: rgba(242, 196, 109, 0.42);
  border-color: rgba(42, 31, 26, 0.3);
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline__figure {
  margin: 0 0 var(--sp-4);
}

.page-about .about-timeline__figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border-radius: var(--r-md);
  border: 1px solid var(--c-line-soft);
}

.page-about .about-timeline__list {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0 0 0 2rem;
}

.page-about .about-timeline__list::before {
  content: "";
  position: absolute;
  left: 0.45rem;
  top: 0.6rem;
  bottom: 0.6rem;
  width: 2px;
  background: linear-gradient(180deg, var(--c-violet), var(--c-cyan) 58%, transparent);
  opacity: 0.7;
}

.page-about .about-timeline__item {
  position: relative;
  padding-block: 0.15rem;
}

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: -1.95rem;
  top: 1.15rem;
  width: 0.9rem;
  height: 0.9rem;
  border-radius: 50%;
  border: 2px solid var(--c-violet);
  background: var(--c-void);
  box-shadow: 0 0 12px var(--c-glow-violet);
}

.page-about .about-timeline__item--signal::before {
  border-color: var(--c-signal);
  box-shadow: 0 0 14px rgba(255, 107, 74, 0.55);
}

.page-about .about-timeline__node > summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.35rem 0.85rem;
  padding: 0.55rem 0.9rem;
  border-radius: var(--r-sm);
  cursor: pointer;
  list-style: none;
  border: 1px solid transparent;
  transition: background var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .about-timeline__node > summary::-webkit-details-marker {
  display: none;
}

.page-about .about-timeline__node > summary:hover,
.page-about .about-timeline__node > summary:focus-visible {
  border-color: var(--c-line);
  background: rgba(17, 26, 51, 0.7);
  outline: none;
}

.page-about .about-timeline__node[open] > summary {
  background: rgba(17, 26, 51, 0.6);
  border-color: var(--c-line-soft);
}

.page-about .about-timeline__ver {
  font-family: var(--font-mono);
  font-size: 1.05rem;
  letter-spacing: var(--track-mono);
  color: var(--c-cyan);
}

.page-about .about-timeline__item--signal .about-timeline__ver {
  color: var(--c-signal);
}

.page-about .about-timeline__name {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: var(--fs-sub);
  letter-spacing: 0.03em;
  color: var(--c-starlight);
}

.page-about .about-timeline__node p {
  margin: 0.35rem 0 0.6rem 0.9rem;
  padding-left: 0.9rem;
  border-left: 1px solid var(--c-line-soft);
  font-size: var(--fs-note);
  line-height: 1.8;
  color: var(--c-mist);
}

/* ---------- 团队与伙伴 ---------- */
.page-about .about-team {
  display: grid;
  gap: var(--sp-4);
  min-width: 0;
}

.page-about .about-team__intro p {
  font-size: var(--fs-body);
  color: var(--c-starlight);
}

.page-about .about-team__intro p + p {
  font-size: var(--fs-note);
  color: var(--c-mist);
  line-height: 1.85;
}

.page-about .about-team__figure {
  margin: 0;
  min-width: 0;
}

.page-about .about-team__figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border-radius: var(--r-md);
  border: 1px solid var(--c-line-soft);
}

.page-about .about-team__bars {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.5rem;
  margin-top: var(--sp-4);
}

.page-about .about-team__bar {
  display: flex;
  align-items: baseline;
  gap: 0.7rem;
  padding: 0.85rem 1rem;
  border-radius: var(--r-md);
  border: 1px solid var(--c-line-soft);
  background: rgba(7, 11, 24, 0.6);
}

.page-about .about-team__bar--a {
  background: linear-gradient(120deg, rgba(69, 240, 224, 0.16), rgba(7, 11, 24, 0.6));
}

.page-about .about-team__bar--b {
  background: linear-gradient(120deg, rgba(185, 167, 255, 0.16), rgba(7, 11, 24, 0.6));
}

.page-about .about-team__bar--c {
  background: linear-gradient(120deg, rgba(242, 196, 109, 0.16), rgba(7, 11, 24, 0.6));
}

.page-about .about-team__bar--d {
  background: linear-gradient(120deg, rgba(138, 148, 184, 0.16), rgba(7, 11, 24, 0.6));
}

.page-about .about-team__bar-num {
  font-family: var(--font-mono);
  font-size: 1.5rem;
  letter-spacing: 0.08em;
  color: var(--c-starlight);
}

.page-about .about-team__bar-label {
  font-size: var(--fs-note);
  color: var(--c-mist);
  letter-spacing: 0.04em;
}

.page-about .about-partners {
  margin-top: var(--sp-4);
  padding-top: var(--sp-3);
  border-top: 1px solid var(--c-line-soft);
}

.page-about .about-partners__lead {
  font-size: var(--fs-note);
  line-height: 1.85;
  color: var(--c-mist);
  max-width: 52em;
}

.page-about .about-partners__list {
  list-style: none;
  margin: 0 0 1.25rem;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.page-about .about-partners__list li {
  padding: 0.35rem 0.85rem;
  border-radius: var(--r-pill);
  border: 1px solid var(--c-line);
  font-size: var(--fs-note);
  color: var(--c-violet);
}

.page-about .about-partners__cta {
  display: inline-block;
}

/* ---------- 覆盖与荣誉 ---------- */
.page-about .about-stats {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: var(--c-line-soft);
  border: 1px solid var(--c-line-soft);
  border-radius: var(--r-md);
  overflow: hidden;
}

.page-about .about-stat {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
  padding: 1.15rem 1.1rem;
  background: var(--c-void);
}

.page-about .about-stat__num {
  font-family: var(--font-head);
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: 800;
  letter-spacing: 0.02em;
  line-height: 1.1;
  color: var(--c-cyan);
}

.page-about .about-stat:nth-child(2n) .about-stat__num {
  color: var(--c-gold);
}

.page-about .about-stat:nth-child(3n) .about-stat__num {
  color: var(--c-violet);
}

.page-about .about-stat__label {
  font-size: var(--fs-note);
  line-height: 1.6;
  color: var(--c-mist);
}

.page-about .about-honor {
  margin: 1.25rem 0 0;
  padding: 1rem 1.15rem;
  border-left: 3px solid var(--c-gold);
  border-radius: 0 var(--r-sm) var(--r-sm) 0;
  background: rgba(242, 196, 109, 0.08);
  font-size: var(--fs-note);
  line-height: 1.85;
  color: var(--c-starlight);
}

/* ---------- 问答 ---------- */
.page-about .about-chapter--faq .about-faq__item {
  border-bottom: 1px solid rgba(42, 31, 26, 0.18);
}

.page-about .about-chapter--faq .about-faq__item:first-child {
  border-top: 1px solid rgba(42, 31, 26, 0.18);
}

.page-about .about-faq__q {
  display: flex;
  align-items: baseline;
  gap: 0.6rem;
  padding: 0.9rem 0;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-head);
  font-size: var(--fs-sub);
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--c-ink);
}

.page-about .about-faq__q::-webkit-details-marker {
  display: none;
}

.page-about .about-faq__q::before {
  content: "Q";
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  letter-spacing: 0.1em;
  color: var(--c-signal);
}

.page-about .about-faq__q:focus-visible {
  outline: 2px solid var(--c-signal);
  outline-offset: 3px;
}

.page-about .about-faq__a {
  margin: 0 0 1rem 1.5rem;
  font-size: var(--fs-note);
  line-height: 1.85;
  color: rgba(42, 31, 26, 0.78);
}

/* ---------- 下一步 ---------- */
.page-about .about-next {
  margin-top: clamp(2rem, 5vw, 3.5rem);
  padding: clamp(1.5rem, 4vw, 2.5rem);
  border-radius: var(--r-lg);
  border: 1px solid var(--c-line);
  background:
    radial-gradient(70% 90% at 100% 0%, rgba(185, 167, 255, 0.16), transparent 70%),
    rgba(17, 26, 51, 0.7);
}

.page-about .about-next__title {
  margin: 0 0 1.25rem;
  font-family: var(--font-head);
  font-size: var(--fs-sub);
  letter-spacing: var(--track-head);
  color: var(--c-starlight);
}

.page-about .about-next__links {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.6rem;
}

.page-about .about-next__link {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.85rem 1.1rem;
  border-radius: var(--r-pill);
  border: 1px solid var(--c-line-soft);
  background: rgba(7, 11, 24, 0.55);
  color: var(--c-starlight);
  font-size: var(--fs-note);
  text-decoration: none;
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .about-next__link::after {
  content: "→";
  margin-left: auto;
  color: var(--c-cyan);
  font-family: var(--font-mono);
}

.page-about .about-next__link:hover,
.page-about .about-next__link:focus-visible {
  border-color: var(--c-cyan);
  color: var(--c-cyan);
  transform: translateX(3px);
  outline: none;
}

/* ---------- 动效 ---------- */
@keyframes about-rise {
  from {
    opacity: 0;
    transform: translateY(18px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (prefers-reduced-motion: no-preference) {
  .page-about .about-hero__copy > * {
    animation: about-rise 620ms var(--ease) both;
  }
  .page-about .about-hero__copy > *:nth-child(2) {
    animation-delay: 90ms;
  }
  .page-about .about-hero__copy > *:nth-child(3) {
    animation-delay: 160ms;
  }
  .page-about .about-hero__copy > *:nth-child(4) {
    animation-delay: 220ms;
  }
  .page-about .about-hero__copy > *:nth-child(5) {
    animation-delay: 280ms;
  }
  .page-about .about-hero__figure {
    animation: about-rise 760ms var(--ease) 200ms both;
  }
}

@supports (animation-timeline: view()) {
  @media (prefers-reduced-motion: no-preference) {
    .page-about .about-chapter__head,
    .page-about .about-origin__point,
    .page-about .about-stat {
      animation: about-rise linear both;
      animation-timeline: view();
      animation-range: entry 5% cover 26%;
    }
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about * {
    animation: none !important;
    transition: none !important;
    scroll-behavior: auto !important;
  }
}

/* ---------- 断点 ---------- */
@media (min-width: 560px) {
  .page-about .about-stats {
    grid-template-columns: repeat(2, 1fr);
  }
  .page-about .about-next__links {
    grid-template-columns: repeat(2, 1fr);
  }
  .page-about .about-origin__points {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 760px) {
  .page-about .about-method {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 0.65fr);
    align-items: start;
  }
  .page-about .about-team__bars {
    grid-template-columns: 6fr 3fr 3fr 2fr;
  }
  .page-about .about-team__bar {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.2rem;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.02fr) minmax(0, 0.98fr);
    align-items: center;
    gap: clamp(2rem, 5vw, 4rem);
  }
  .page-about .about-team {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
    align-items: center;
  }
  .page-about .about-stats {
    grid-template-columns: repeat(3, 1fr);
  }
  .page-about .about-next__links {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1000px) {
  .page-about .about-layout {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    align-items: start;
  }
  .page-about .about-rail {
    position: sticky;
    top: calc(var(--header-h) + 1rem);
    padding: 1.1rem 1.1rem 1.2rem;
  }
  .page-about .about-rail .side-rail__list {
    flex-direction: column;
    gap: 0.15rem;
    overflow-x: visible;
  }
  .page-about .about-rail .side-rail__link {
    white-space: normal;
    border-radius: var(--r-sm);
    border-left: 2px solid transparent;
  }
  .page-about .about-rail .side-rail__link:hover,
  .page-about .about-rail .side-rail__link:focus-visible {
    background: rgba(69, 240, 224, 0.12);
    border-color: transparent;
    border-left-color: var(--c-cyan);
    color: var(--c-cyan);
  }
  .page-about .about-origin {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    gap: clamp(1.5rem, 3.5vw, 2.75rem);
    align-items: start;
  }
  .page-about .about-origin__points {
    grid-template-columns: 1fr;
  }
  .page-about .about-stat {
    padding: 1.4rem 1.3rem;
  }
}